1. Field of the Invention
The present invention relates to a microwave oven and, in particular, to a cooking chamber cavity structure for microwave ovens.
2. Description of the Prior Art
A conventional microwave oven, as illustrated in FIGS. 1 and 2, includes: a partition wall 5 formed in a "U" shape for partitioning off the microwave oven into a cooking chamber 1 and a machine room 3; a top plate 6 disposed at an upper side of the partion wall 5 for covering a cooking chamber; a rear panel 7 assembled at one side of the partition wall 5 to house the cooking chamber 1 and the machine room 3; a front panel 9 disposed at the other side of the partion wall 5; and a bottom plate 11 placed beneath a bottom of the partition wall 5, thus supporting the bottom of the partition wall 5 and at the same time, mounted thereon with various electronic parts.
The front panel 9 is formed at one side thereof with an opening 9a for receiving foods therethrough into the cooking chamber 1. The front panel 9 formed with the opening 9a is provided at one side thereof a door member 13, thereby opening or closing the cooking chamber 1. The cooking chamber is removably mounted at a floor thereof with a turntable 15 for placing foods thereon.
The machine room 3 is mounted at one side thereof with a high frequency generating means 17 for generating a high voltage. The machine room is also provided at one side thereof with a magnetron 19 for generating a high frequency when a high voltage generated by the high frequency generating means 17 is applied thereto.
The magnetron 19 and the partition are assembled at their upper sides with a waveguide 21 for guiding high frequency produced by the magnetron into the cooking chamber. The rear panel 7 is provided at one side thereof with a fan 23, which allows air to flow into and to be discharged outside the microwave oven after circulation of the air therein when electric power is supplied thereto, thereby cooling an inner side of the microwave oven.
Furthermore, a lateral wall of the cooking chamber 1 is formed at an upper side thereof with a number of outlets 5a for serving to discharge the air therethrough after its circulation. The front panel 9 is disposed at a side of the machine room with an exterior duct 25 for discharging the air infused into the machine room 3 toward a kitchen.
The exterior duct 25 is mounted at above a control unit 27 provided with a manipulating button, by which a driving condition, heating time and the like are selected.
In order to drive the microwave oven thus constructed, first, the door 13 is opened and food F is placed on the turntable disposed on the floor of the cooking chamber 1, thereafter the door 13 is closed, desired cooking time and cooking menu and the like are input by the control unit 27, and a start button is pressed. Then the turntable 15 is rotated in one direction as a high frequency is generated according to an oscillating operation of a magnetron (not shown) to thereafter be dispersed in the cooking chamber 1.
The high frequency dispersed in the cooking chamber 1 is reflected from metal walls therein and is radiated to the food on the turntable 15 to thereby heat the food.
At this time, a heat generated by operations of the high frequency generating means 17 and magnetron 19 is cooled by an exterior air flowing into the machine room 3 through a number of inlets 7a formed in the rear panel 7 when the fan 23 is operated by electric power applied thereto, and the air is discharged through the exterior duct 25 outside the oven thereafter.
Meanwhile, some exterior air sucked through the inlet 7a formed at the rear panel 7 flows into the cooking chamber 1 and cool the heated air, thereafter being discharged toward the outside the oven through a number of outlets 5a formed at an upper side of the wall of the cooking chamber 1.
However, there is a problem in the conventional microwave oven thus constructed in that as the cooking chamber cavity structure requires five parts, that is, the partition wall 5, the top plate 6, the front panel 9, the rear panel 7, and the bottom plate 11 to form the cooking chamber 1, the cavity structure wastes material and increases the manufacturing cost.